Wallet file encryption:

- a keypair is derived from the wallet password
 - only the public key is retained in memory
 - wallets must opened and closed explicitly with the daemon

electrum

@@ -179,7 +179,27 @@ def run_non_RPC(config):
     sys.exit(0)
 
 
-def init_cmdline(config_options):
+def init_daemon(config_options):
+    config = SimpleConfig(config_options)
+    storage = WalletStorage(config.get_wallet_path())
+    if not storage.file_exists:
+        print_msg("Error: Wallet file not found.")
+        print_msg("Type 'electrum create' to create a new wallet, or provide a path to a wallet with the -w option")
+        sys.exit(0)
+    if storage.is_encrypted():
+        if config.get('password'):
+            password = config.get('password')
+        else:
+            password = prompt_password('Password:', False)
+            if not password:
+                print_msg("Error: Password required")
+                sys.exit(1)
+    else:
+        password = None
+    config_options['password'] = password
+
+
+def init_cmdline(config_options, server):
     config = SimpleConfig(config_options)
     cmdname = config.get('cmd')
     cmd = known_commands[cmdname]
@@ -208,8 +228,11 @@ def init_cmdline(config_options):
         print_stderr("Exposing a single private key can compromise your entire wallet!")
         print_stderr("In particular, DO NOT use 'redeem private key' services proposed by third parties.")
 
+    if not storage.is_encrypted():
+        storage.read(None)
     # commands needing password
-    if cmd.requires_password and storage.get('use_encryption'):
+    if (storage.is_encrypted() and server is None)\
+       or (cmd.requires_password and (storage.get('use_encryption') or storage.is_encrypted())):
         if config.get('password'):
             password = config.get('password')
         else:
@@ -232,18 +255,19 @@ def init_cmdline(config_options):
 def run_offline_command(config, config_options):
     cmdname = config.get('cmd')
     cmd = known_commands[cmdname]
+    password = config_options.get('password')
     storage = WalletStorage(config.get_wallet_path())
+    storage.read(password if storage.is_encrypted() else None)
     wallet = Wallet(storage) if cmd.requires_wallet else None
     # check password
     if cmd.requires_password and storage.get('use_encryption'):
-        password = config_options.get('password')
         try:
             seed = wallet.check_password(password)
         except InvalidPassword:
             print_msg("Error: This password does not decode this wallet.")
             sys.exit(1)
     if cmd.requires_network:
-        print_stderr("Warning: running command offline")
+        print_msg("Warning: running command offline")
     # arguments passed to function
     args = map(lambda x: config.get(x), cmd.params)
     # decode json arguments
@@ -347,7 +371,9 @@ if __name__ == '__main__':
 
     elif cmdname == 'daemon':
         subcommand = config.get('subcommand')
-        assert subcommand in [None, 'start', 'stop', 'status']
+        if subcommand in ['open']:
+            init_daemon(config_options)
+
         if subcommand in [None, 'start']:
             fd, server = daemon.get_fd_or_server(config)
             if fd is not None:
@@ -377,8 +403,8 @@ if __name__ == '__main__':
                 sys.exit(1)
     else:
         # command line
-        init_cmdline(config_options)
         server = daemon.get_server(config)
+        init_cmdline(config_options, server)
         if server is not None:
             result = server.run_cmdline(config_options)
         else:

gui/qt/__init__.py

@@ -159,18 +159,26 @@ class ElectrumGui:
                 w.bring_to_top()
                 break
         else:
-            try:
-                wallet = self.daemon.load_wallet(path)
-            except BaseException as e:
-                QMessageBox.information(None, _('Error'), str(e), _('OK'))
-                return
-            if wallet is None:
+            if not os.path.exists(path):
                 wizard = InstallWizard(self.config, self.app, self.plugins, path)
                 wallet = wizard.run_and_get_wallet()
                 if not wallet:
                     return
                 wallet.start_threads(self.daemon.network)
                 self.daemon.add_wallet(wallet)
+            else:
+                from password_dialog import PasswordDialog
+                msg = _("The file '%s' is encrypted.") % os.path.basename(path)
+                password_getter = lambda: PasswordDialog(msg=msg).run()
+                while True:
+                    try:
+                        wallet = self.daemon.load_wallet(path, password_getter)
+                        break
+                    except UserCancelled:
+                        return
+                    except BaseException as e:
+                        QMessageBox.information(None, _('Error'), str(e), _('OK'))
+                        continue
             w = self.create_window_for_wallet(wallet)
         if uri:
             w.pay_to_URI(uri)

gui/qt/installwizard.py

@@ -294,8 +294,9 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
 
     def pw_layout(self, msg, kind):
         playout = PasswordLayout(None, msg, kind, self.next_button)
+        playout.encrypt_cb.setChecked(True)
         self.set_main_layout(playout.layout())
-        return playout.new_password()
+        return playout.new_password(), playout.encrypt_cb.isChecked()
 
     @wizard_dialog
     def request_password(self, run_next):

gui/qt/main_window.py

@@ -1680,19 +1680,13 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
         self.send_button.setVisible(not self.wallet.is_watching_only())
 
     def change_password_dialog(self):
-        from password_dialog import PasswordDialog, PW_CHANGE
-
-        msg = (_('Your wallet is encrypted. Use this dialog to change your '
-                 'password. To disable wallet encryption, enter an empty new '
-                 'password.') if self.wallet.has_password()
-               else _('Your wallet keys are not encrypted'))
-        d = PasswordDialog(self, self.wallet, msg, PW_CHANGE)
-        ok, password, new_password = d.run()
+        from password_dialog import ChangePasswordDialog
+        d = ChangePasswordDialog(self, self.wallet)
+        ok, password, new_password, encrypt_file = d.run()
         if not ok:
             return
-
         try:
-            self.wallet.update_password(password, new_password)
+            self.wallet.update_password(password, new_password, encrypt_file)
         except BaseException as e:
             self.show_error(str(e))
             return
@@ -1700,8 +1694,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             traceback.print_exc(file=sys.stdout)
             self.show_error(_('Failed to update password'))
             return
-
-        msg = _('Password was updated successfully') if new_password else _('This wallet is not encrypted')
+        msg = _('Password was updated successfully') if new_password else _('Password is disabled, this wallet is not protected')
         self.show_message(msg, title=_("Success"))
         self.update_lock_icon()
 
@@ -1972,24 +1965,10 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
         d.exec_()
 
     def password_dialog(self, msg=None, parent=None):
+        from password_dialog import PasswordDialog
         parent = parent or self
-        d = WindowModalDialog(parent, _("Enter Password"))
-        pw = QLineEdit()
-        pw.setEchoMode(2)
-        vbox = QVBoxLayout()
-        if not msg:
-            msg = _('Please enter your password')
-        vbox.addWidget(QLabel(msg))
-        grid = QGridLayout()
-        grid.setSpacing(8)
-        grid.addWidget(QLabel(_('Password')), 1, 0)
-        grid.addWidget(pw, 1, 1)
-        vbox.addLayout(grid)
-        vbox.addLayout(Buttons(CancelButton(d), OkButton(d)))
-        d.setLayout(vbox)
-        run_hook('password_dialog', pw, grid, 1)
-        if not d.exec_(): return
-        return unicode(pw.text())
+        d = PasswordDialog(parent, msg)
+        return d.run()
 
 
     def tx_from_text(self, txt):

gui/qt/password_dialog.py

@@ -30,6 +30,8 @@ from util import *
 import re
 import math
 
+from electrum.plugins import run_hook
+
 def check_password_strength(password):
 
     '''
@@ -92,7 +94,7 @@ class PasswordLayout(object):
             logo_grid.addWidget(label, 0, 1, 1, 2)
             vbox.addLayout(logo_grid)
 
-            m1 = _('New Password:') if kind == PW_NEW else _('Password:')
+            m1 = _('New Password:') if kind == PW_CHANGE else _('Password:')
             msgs = [m1, _('Confirm Password:')]
             if wallet and wallet.has_password():
                 grid.addWidget(QLabel(_('Current Password:')), 0, 0)
@@ -115,8 +117,15 @@ class PasswordLayout(object):
             grid.addWidget(self.pw_strength, 3, 0, 1, 2)
             self.new_pw.textChanged.connect(self.pw_changed)
 
+        self.encrypt_cb = QCheckBox(_('Encrypt wallet file'))
+        self.encrypt_cb.setEnabled(False)
+        grid.addWidget(self.encrypt_cb, 4, 0, 1, 2)
+        self.encrypt_cb.setVisible(kind != PW_PASSPHRASE)
+
         def enable_OK():
-            OK_button.setEnabled(self.new_pw.text() == self.conf_pw.text())
+            ok = self.new_pw.text() == self.conf_pw.text()
+            OK_button.setEnabled(ok)
+            self.encrypt_cb.setEnabled(ok and bool(self.new_pw.text()))
         self.new_pw.textChanged.connect(enable_OK)
         self.conf_pw.textChanged.connect(enable_OK)
 
@@ -153,20 +162,54 @@ class PasswordLayout(object):
         return pw
 
 
-class PasswordDialog(WindowModalDialog):
+class ChangePasswordDialog(WindowModalDialog):
 
-    def __init__(self, parent, wallet, msg, kind):
+    def __init__(self, parent, wallet):
         WindowModalDialog.__init__(self, parent)
+        is_encrypted = wallet.storage.is_encrypted()
+        if not wallet.has_password():
+            msg = _('Your wallet is not protected.')
+            msg += ' ' + _('Use this dialog to add a password to your wallet.')
+        else:
+            if not is_encrypted:
+                msg = _('Your bitcoins are password protected. However, your wallet file is not encrypted.')
+            else:
+                msg = _('Your wallet is password protected and encrypted.')
+            msg += ' ' + _('Use this dialog to change your password.')
         OK_button = OkButton(self)
-        self.playout = PasswordLayout(wallet, msg, kind, OK_button)
+        self.playout = PasswordLayout(wallet, msg, PW_CHANGE, OK_button)
         self.setWindowTitle(self.playout.title())
         vbox = QVBoxLayout(self)
         vbox.addLayout(self.playout.layout())
         vbox.addStretch(1)
         vbox.addLayout(Buttons(CancelButton(self), OK_button))
+        self.playout.encrypt_cb.setChecked(is_encrypted or not wallet.has_password())
 
     def run(self):
         if not self.exec_():
-            return False, None, None
+            return False, None, None, None
+        return True, self.playout.old_password(), self.playout.new_password(), self.playout.encrypt_cb.isChecked()
+
+
+class PasswordDialog(WindowModalDialog):
 
-        return True, self.playout.old_password(), self.playout.new_password()
+    def __init__(self, parent=None, msg=None):
+        msg = msg or _('Please enter your password')
+        WindowModalDialog.__init__(self, parent, _("Enter Password"))
+        self.pw = pw = QLineEdit()
+        pw.setEchoMode(2)
+        vbox = QVBoxLayout()
+        vbox.addWidget(QLabel(msg))
+        grid = QGridLayout()
+        grid.setSpacing(8)
+        grid.addWidget(QLabel(_('Password')), 1, 0)
+        grid.addWidget(pw, 1, 1)
+        vbox.addLayout(grid)
+        vbox.addLayout(Buttons(CancelButton(self), OkButton(self)))
+        self.setLayout(vbox)
+        run_hook('password_dialog', pw, grid, 1)
+
+    def run(self):
+        if not self.exec_():
+            return
+        return unicode(self.pw.text())

gui/stdio.py

@@ -19,6 +19,8 @@ class ElectrumGui:
         if not storage.file_exists:
             print "Wallet not found. try 'electrum create'"
             exit()
+        password = getpass.getpass('Password:', stream=None) if storage.is_encrypted() else None
+        storage.read(password)
 
         self.done = 0
         self.last_balance = ""

gui/text.py

@@ -1,6 +1,7 @@
 import tty, sys
 import curses, datetime, locale
 from decimal import Decimal
+import getpass
 
 from electrum.util import format_satoshis, set_verbosity
 from electrum.util import StoreDict
@@ -21,7 +22,8 @@ class ElectrumGui:
         if not storage.file_exists:
             print "Wallet not found. try 'electrum create'"
             exit()
-
+        password = getpass.getpass('Password:', stream=None) if storage.is_encrypted() else None
+        storage.read(password)
         self.wallet = Wallet(storage)
         self.wallet.start_threads(self.network)
         self.contacts = StoreDict(self.config, 'contacts')

lib/base_wizard.py

@@ -331,8 +331,8 @@ class BaseWizard(object):
         else:
             self.on_password(None)
 
-    def on_password(self, password):
-        self.storage.put('use_encryption', bool(password))
+    def on_password(self, password, encrypt):
+        self.storage.set_password(password, encrypt)
         for k in self.keystores:
             if k.may_have_password():
                 k.update_password(None, password)

lib/bitcoin.py

@@ -653,34 +653,26 @@ class EC_KEY(object):
 
 
     def decrypt_message(self, encrypted):
-
         encrypted = base64.b64decode(encrypted)
-
         if len(encrypted) < 85:
             raise Exception('invalid ciphertext: length')
-
         magic = encrypted[:4]
         ephemeral_pubkey = encrypted[4:37]
         ciphertext = encrypted[37:-32]
         mac = encrypted[-32:]
-
         if magic != 'BIE1':
             raise Exception('invalid ciphertext: invalid magic bytes')
-
         try:
             ephemeral_pubkey = ser_to_point(ephemeral_pubkey)
         except AssertionError, e:
             raise Exception('invalid ciphertext: invalid ephemeral pubkey')
-
         if not ecdsa.ecdsa.point_is_valid(generator_secp256k1, ephemeral_pubkey.x(), ephemeral_pubkey.y()):
             raise Exception('invalid ciphertext: invalid ephemeral pubkey')
-
         ecdh_key = point_to_ser(ephemeral_pubkey * self.privkey.secret_multiplier)
         key = hashlib.sha512(ecdh_key).digest()
         iv, key_e, key_m = key[0:16], key[16:32], key[32:]
         if mac != hmac.new(key_m, encrypted[:-32], hashlib.sha256).digest():
-            raise Exception('invalid ciphertext: invalid mac')
-
+            raise InvalidPassword()
         return aes_decrypt_with_iv(key_e, iv, ciphertext)
 
 

lib/commands.py

@@ -796,7 +796,7 @@ def get_parser():
     add_global_options(parser_gui)
     # daemon
     parser_daemon = subparsers.add_parser('daemon', help="Run Daemon")
-    parser_daemon.add_argument("subcommand", choices=['start', 'status', 'stop'], nargs='?')
+    parser_daemon.add_argument("subcommand", choices=['start', 'status', 'stop', 'open', 'close'], nargs='?')
     #parser_daemon.set_defaults(func=run_daemon)
     add_network_options(parser_daemon)
     add_global_options(parser_daemon)

lib/daemon.py

@@ -34,7 +34,7 @@ from jsonrpclib.SimpleJSONRPCServer import SimpleJSONRPCServer, SimpleJSONRPCReq
 from version import ELECTRUM_VERSION
 from network import Network
 from util import json_decode, DaemonThread
-from util import print_msg, print_error, print_stderr
+from util import print_msg, print_error, print_stderr, UserCancelled
 from wallet import WalletStorage, Wallet
 from commands import known_commands, Commands
 from simple_config import SimpleConfig
@@ -115,8 +115,7 @@ class Daemon(DaemonThread):
         self.gui = None
         self.wallets = {}
         # Setup JSONRPC server
-        path = config.get_wallet_path()
-        default_wallet = self.load_wallet(path)
+        default_wallet = None
         self.cmd_runner = Commands(self.config, default_wallet, self.network)
         self.init_server(config, fd)
 
@@ -145,11 +144,24 @@ class Daemon(DaemonThread):
     def ping(self):
         return True
 
-    def run_daemon(self, config):
+    def run_daemon(self, config_options):
+        config = SimpleConfig(config_options)
         sub = config.get('subcommand')
-        assert sub in [None, 'start', 'stop', 'status']
+        assert sub in [None, 'start', 'stop', 'status', 'open', 'close']
         if sub in [None, 'start']:
             response = "Daemon already running"
+        elif sub == 'open':
+            path = config.get_wallet_path()
+            self.load_wallet(path, lambda: config.get('password'))
+            response = True
+        elif sub == 'close':
+            path = config.get_wallet_path()
+            if path in self.wallets:
+                wallet = self.wallets.pop(path)
+                wallet.stop_threads()
+                response = True
+            else:
+                response = False
         elif sub == 'status':
             if self.network:
                 p = self.network.get_parameters()
@@ -185,7 +197,7 @@ class Daemon(DaemonThread):
             response = "Error: Electrum is running in daemon mode. Please stop the daemon first."
         return response
 
-    def load_wallet(self, path):
+    def load_wallet(self, path, password_getter):
         # wizard will be launched if we return
         if path in self.wallets:
             wallet = self.wallets[path]
@@ -193,6 +205,13 @@ class Daemon(DaemonThread):
         storage = WalletStorage(path)
         if not storage.file_exists:
             return
+        if storage.is_encrypted():
+            password = password_getter()
+            if not password:
+                raise UserCancelled()
+        else:
+            password = None
+        storage.read(password)
         if storage.requires_split():
             return
         if storage.requires_upgrade():
@@ -214,20 +233,25 @@ class Daemon(DaemonThread):
         wallet.stop_threads()
 
     def run_cmdline(self, config_options):
+        password = config_options.get('password')
+        new_password = config_options.get('new_password')
         config = SimpleConfig(config_options)
         cmdname = config.get('cmd')
         cmd = known_commands[cmdname]
-        path = config.get_wallet_path()
-        wallet = self.load_wallet(path) if cmd.requires_wallet else None
+        if cmd.requires_wallet:
+            path = config.get_wallet_path()
+            wallet = self.wallets.get(path)
+            if wallet is None:
+                return {'error': 'Wallet not open. Use "electrum daemon open -w wallet"'}
+        else:
+            wallet = None
         # arguments passed to function
         args = map(lambda x: config.get(x), cmd.params)
         # decode json arguments
         args = map(json_decode, args)
         # options
         args += map(lambda x: config.get(x), cmd.options)
-        cmd_runner = Commands(config, wallet, self.network,
-                              password=config_options.get('password'),
-                              new_password=config_options.get('new_password'))
+        cmd_runner = Commands(config, wallet, self.network, password=password, new_password=new_password)
         func = getattr(cmd_runner, cmd.name)
         result = func(*args)
         return result

lib/storage.py

@@ -32,11 +32,15 @@ import json
 import copy
 import re
 import stat
+import pbkdf2, hmac, hashlib
+import base64
+import zlib
 
 from i18n import _
 from util import NotEnoughFunds, PrintError, profiler
 from plugins import run_hook, plugin_loaders
 from keystore import bip44_derivation
+import bitcoin
 
 
 # seed_version is now used for the version of the wallet file
@@ -63,50 +67,57 @@ class WalletStorage(PrintError):
         self.lock = threading.RLock()
         self.data = {}
         self.path = path
-        self.file_exists = False
+        self.file_exists = os.path.exists(self.path)
         self.modified = False
-        self.print_error("wallet path", self.path)
-        if self.path:
-            self.read(self.path)
+        self.pubkey = None
         # check here if I need to load a plugin
         t = self.get('wallet_type')
         l = plugin_loaders.get(t)
         if l: l()
 
+    def decrypt(self, s, password):
+        # Note: hardware wallets should use a seed-derived key and not require a password.
+        # Thus, we need to expose keystore metadata
+        if password is None:
+            self.pubkey = None
+            return s
+        secret = pbkdf2.PBKDF2(password, '', iterations = 1024, macmodule = hmac, digestmodule = hashlib.sha512).read(64)
+        ec_key = bitcoin.EC_KEY(secret)
+        self.pubkey = ec_key.get_public_key()
+        return zlib.decompress(ec_key.decrypt_message(s)) if s else None
+
+    def set_password(self, pw, encrypt):
+        """Set self.pubkey"""
+        self.put('use_encryption', (pw is not None))
+        self.decrypt(None, pw if encrypt else None)
+
+    def is_encrypted(self):
+        try:
+            with open(self.path, "r") as f:
+                s = f.read(8)
+        except IOError:
+            return
+        try:
+            return base64.b64decode(s).startswith('BIE1')
+        except:
+            return False
 
-    def read(self, path):
+    def read(self, password):
         """Read the contents of the wallet file."""
+        self.print_error("wallet path", self.path)
         try:
             with open(self.path, "r") as f:
-                data = f.read()
+                s = f.read()
         except IOError:
             return
-        if not data:
+        if not s:
             return
+        # Decrypt wallet.
+        s = self.decrypt(s, password)
         try:
-            self.data = json.loads(data)
+            self.data = json.loads(s)
         except:
-            try:
-                d = ast.literal_eval(data)  #parse raw data from reading wallet file
-                labels = d.get('labels', {})
-            except Exception as e:
-                raise IOError("Cannot read wallet file '%s'" % self.path)
-            self.data = {}
-            # In old versions of Electrum labels were latin1 encoded, this fixes breakage.
-            for i, label in labels.items():
-                try:
-                    unicode(label)
-                except UnicodeDecodeError:
-                    d['labels'][i] = unicode(label.decode('latin1'))
-            for key, value in d.items():
-                try:
-                    json.dumps(key)
-                    json.dumps(value)
-                except:
-                    self.print_error('Failed to convert label to json format', key)
-                    continue
-                self.data[key] = value
-        self.file_exists = True
+            raise IOError("Cannot read wallet file '%s'" % self.path)
 
     def get(self, key, default=None):
         with self.lock:
@@ -133,6 +144,7 @@ class WalletStorage(PrintError):
                 self.modified = True
                 self.data.pop(key)
 
+    @profiler
     def write(self):
         # this ensures that previous versions of electrum won't open the wallet
         self.put('seed_version', FINAL_SEED_VERSION)
@@ -147,6 +159,9 @@ class WalletStorage(PrintError):
         if not self.modified:
             return
         s = json.dumps(self.data, indent=4, sort_keys=True)
+        if self.pubkey:
+            s = bitcoin.encrypt_message(zlib.compress(s), self.pubkey)
+
         temp_path = "%s.tmp.%s" % (self.path, os.getpid())
         with open(temp_path, "w") as f:
             f.write(s)

lib/wallet.py

@@ -1577,10 +1577,10 @@ class Simple_Deterministic_Wallet(Deterministic_Wallet, Simple_Wallet):
     def check_password(self, password):
         self.keystore.check_password(password)
 
-    def update_password(self, old_pw, new_pw):
+    def update_password(self, old_pw, new_pw, encrypt=False):
         self.keystore.update_password(old_pw, new_pw)
         self.save_keystore()
-        self.storage.put('use_encryption', (new_pw is not None))
+        self.storage.set_password(new_pw, encrypt)
         self.storage.write()
 
     def save_keystore(self):
@@ -1686,7 +1686,7 @@ class Multisig_Wallet(Deterministic_Wallet, P2SH):
             if keystore.can_change_password():
                 keystore.update_password(old_pw, new_pw)
                 self.storage.put(name, keystore.dump())
-        self.storage.put('use_encryption', (new_pw is not None))
+        self.storage.set_password(new_pw)
 
     def check_password(self, password):
         self.keystore.check_password(password)